Sony DRX-840U 20x External Dual-Layer DVD Burner Media & Modes Supported - DVD-R/-R DL/-RW, DVD+R/DVD+R DL/+RW, DVD-ROM, DVD-Video, CD-DA, CD-ROM (XA), CD Extra, Video CD, Photo CD1 and CD Text Sustained Transfer Rate - 21MB/s (16x DVD-ROM) Burst Transfer Rate - 480MB/s Average Access Time - 130ms (DVD 16x), 110ms (CD 48x) System Requirements - 10GB Hard Drive, Windows Vista, Windows XP Home or Professional (SP2) Operating Systems or Windows 2000 (SP4) Operating Systems, 256MB RAM, Pentium III 800MHz or faster (or equivalent) CPU minimum Processor, Pentium IV 2.0GHz or faster (or equivalent) CPU is recommended for real-time video authoring/editing